Interactive Maps

The Lower Potomac

The Potomac Estuary

Mount Vernon to Anacostia River

Mall Area

Georgetown to Great Falls

Potomac Piedmont

Upper Potomac

The North Branch

Boat Ramps

Monitoring Sites

Bridges and Ferries

Cruises and Charters

Search Potomac Sites

Also Explore

Monocacy River

Maryland Tributary

The Monocacy is the third largest tributary of the Potomac, after the Shenendoah River and the Anacostia River. The river flows 58.5 miles starting in northern Maryland, and drains an area of 744 square miles, the largest Maryland tributary to the Potomac. In 1974, the river was designated as a Maryland Scenic River, but it suffers from a serious problem with runoff and sedimentation.

Suggested Links

Contact Information
Maryland Department of Natural Resources

VA

Website